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Characteristic Extraction Tool For Gravitational Waveforms, Maria C. Babiuc-Hamilton, B´ela Szila´gyi, Jeffrey Winicour, Yosef Zlochower 2011 Marshall University, Huntigton, WV

Characteristic Extraction Tool For Gravitational Waveforms, Maria C. Babiuc-Hamilton, B´Ela Szila´Gyi, Jeffrey Winicour, Yosef Zlochower

Physics Faculty Research

We develop and calibrate a characteristic waveform extraction tool whose major improvements and corrections of prior versions allow satisfaction of the accuracy standards required for advanced LIGO data analysis. The extraction tool uses a characteristic evolution code to propagate numerical data on an inner worldtube supplied by a 3+1 Cauchy evolution to obtain the gravitational waveform at null infinity. With the new extraction tool, high accuracy and convergence of the numerical error can be demonstrated for an inspiral and merger of mass M binary black holes even for an extraction worldtube radius as small as R=20M. The …


Comparison Of A High Purity Germanium Gamma Ray Spectrometer And A Multidimensional Nai(T1) Scintillation Gamma Ray Spectrometer, Greg Stratton 2011 California Polytechnic State University, San Luis Obispo

Comparison Of A High Purity Germanium Gamma Ray Spectrometer And A Multidimensional Nai(T1) Scintillation Gamma Ray Spectrometer, Greg Stratton

Aerospace Engineering

This report compares two different gamma ray spectrometers in terms of performance, operation, and apparatus and also investigates the design and integration challenges of using gamma ray spectrometers in space. The first spectrometer is a one-dimensional high purity germanium (HPGe) spectrometer and the second is a multidimensional NaI(Tl) scintillation spectrometer (MGRS). The key results show that the HPGe exhibits 15 to 27 times better energy resolution than the MGRS, but the MGRS is 52 times more sensitive and removes 177 % more of the background radiation.


Variable Renewable Energy In Modeling Climate Change Mitigation Scenarios, Falko Ueckerdt, Robert J. Brecha, Gunnar Luderer, Patrick Sullivan, Eva Schmid, Nico Bauer, Diana Böttger 2011 Potsdam Institute for Climate Impact Research

Variable Renewable Energy In Modeling Climate Change Mitigation Scenarios, Falko Ueckerdt, Robert J. Brecha, Gunnar Luderer, Patrick Sullivan, Eva Schmid, Nico Bauer, Diana Böttger

Physics Faculty Publications

This paper addresses the issue of how to account for short‐term temporal variability of renewable energy sources and power demand in long‐term climate change mitigation scenarios in energy‐economic models. An approach that captures in a stylized way the major challenges to the integration of variable renewable energy sources into power systems has been developed. As a first application this approach has been introduced to REMIND‐D, a hybrid energy‐economy model of Germany. An approximation of the residual load duration curve is implemented. The approximating function endogenously changes depending on the penetration and mix of variable renewable power. The approach can thus …


Saturated Absorption For A Magneto-Optical Atom Trap As A Step Toward Atomic Dipole Traps In A Diffraction Pattern From A Circular Aperture, Andrew Ferdinand 2011 California Polytechnic State University - San Luis Obispo

Saturated Absorption For A Magneto-Optical Atom Trap As A Step Toward Atomic Dipole Traps In A Diffraction Pattern From A Circular Aperture, Andrew Ferdinand

Physics

Neutral atom quantum computing is a promising avenue toward the realization of a physical quantum computer. The diffraction pattern formed by laser light immediately behind a circular aperture can be used as optical atomic dipole traps, and has the potential to be scaled up to create a two dimensional array of individually addressable qubit sites. In working towards experimental demonstration of the dipole traps, we are constructing a MOT. The function of the MOT is to cool and trap 87Rb in a localized cloud in our vacuum chamber, which will be used to load the dipole traps. One critical …


Quantum Mechanics, Quantum Computation, And The Density Operator In Sympy, Addison Cugini 2011 California Polytechnic State University - San Luis Obispo

Quantum Mechanics, Quantum Computation, And The Density Operator In Sympy, Addison Cugini

Physics

Because aspects of quantum mechanics are both difficult to understand and difficult algebraically, there is a need for software which symbolically simulates quantum mechanical phenomena. To accomplish this goal, code has been added to an open-source computer algebra system, called SymPy, which models the abstraction of Dirac notation and the density operator. Additionally, a quantum computer simulation has been built using this abstraction. This paper shall discuss the code that has been added as well as any relevant physics important to understanding the code. In particular, we shall focus on the density operator of statistical quantum mechanics using SymPy's density …


Symbolic Quantum Circuit Simplification In Sympy, Matthew Curry 2011 California Polytechnic State University - San Luis Obispo

Symbolic Quantum Circuit Simplification In Sympy, Matthew Curry

Physics

In the field of quantum information science, one can design a series of quantum logic operations known as a circuit. Circuits are the basis for quantum computations in quantum computing. As circuits will most likely be designed from a logical standpoint, there could exist mathematical redundancies which will lead to a larger circuit than necessary. These redundancies are computationally expensive, and there is a need for them to be found and eliminated to simplify the circuit. We present our research on finding the rules for simplifying circuits and its implementation in SymPy.


Approach To Typicality In Quantum Systems, Shawn Dubey 2011 University of Massachusetts Boston

Approach To Typicality In Quantum Systems, Shawn Dubey

Applied Physics Masters Theses Collection

The study of quantum mechanics has greatly broadened since its inception in the early twentieth century. Recent research has focused on the emergence of thermalization in quantum many-body systems. In this thesis I will demonstrate the approach to typicality--the notion that for specific sets of objects, most of the objects share a common property--in a single, many-body spins chain of spin half particles. This notion of typicality is new. But it serves as a good explanation for the emergence of thermalization.


Quantum Ghost Imaging Through Turbulence, John C. Howell 2011 Chapman University

Quantum Ghost Imaging Through Turbulence, John C. Howell

Mathematics, Physics, and Computer Science Faculty Articles and Research

We investigate the effect of turbulence on quantum ghost imaging. We use entangled photons and demonstrate that for a specific experimental configuration the effect of turbulence can be greatly diminished. By decoupling the entangled photon source from the ghost-imaging central image plane, we are able to dramatically increase the ghost-image quality. When imaging a test pattern through turbulence, this method increases the imaged pattern visibility from V=0.15±0.04 to 0.42±0.04.


The Quantum Dialectic, Logan Kelley 2011 Pitzer College

The Quantum Dialectic, Logan Kelley

Pitzer Senior Theses

A philosophic account of quantum physics. The thesis is divided into two parts. Part I is dedicated to laying the groundwork of quantum physics, and explaining some of the primary difficulties. Subjects of interest will include the principle of locality, the quantum uncertainty principle, and Einstein's criterion for reality. Quantum dilemmas discussed include the double-slit experiment, observations of spin and polarization, EPR, and Bell's theorem. The first part will argue that mathematical-physical descriptions of the world fall short of explaining the experimental observations of quantum phenomenon. The problem, as will be argued, is framework of the physical descriptive schema. Part …


Holism And Non-Separability Applied To Quantum Mechanics, Catherine E. Nisson 2011 James Madison University

Holism And Non-Separability Applied To Quantum Mechanics, Catherine E. Nisson

Senior Honors Projects, 2010-2019

Einstein was never satisfied with quantum mechanics. He argued that quantum mechanics was incomplete for two main reasons; it violated the locality principle and the separability principle. The violation of separability is an unavoidable consequence of quantum interactions. Non-separability can be seen in quantum entanglement. Non-locality, however, is more controversial. Einstein and his associates published the EPR paper in order to argue for the incompleteness of quantum mechanics. Years later, John Bell formulated what became known as the Bell Inequalities in response to the EPR paper. The Bell Inequalities are seen as a major obstacle for quantum locality. I will …


Prioritizing Investment In Residential Energy Efficiency And Renewable Energy: A Case Study For The U.S. Midwest, Robert J. Brecha, Austin Mitchell, Kevin P. Hallinan, J. Kelly Kissock 2011 University of Dayton

Prioritizing Investment In Residential Energy Efficiency And Renewable Energy: A Case Study For The U.S. Midwest, Robert J. Brecha, Austin Mitchell, Kevin P. Hallinan, J. Kelly Kissock

Physics Faculty Publications

Residential building energy use is an important contributor to greenhouse gas emissions and in the United States represents about 20% of total energy consumption. A number of previous macro-scale studies of residential energy consumption and energy-efficiency improvements are mainly concerned with national or international aggregate potential savings. In this paper we look into the details of how a collection of specific homes in one region might reduce energy consumption and carbon emissions, with particular attention given to some practical limits to what can be achieved by upgrading the existing residential building stock. Using a simple model of residential, single-family home …


Entangling The Lattice Clock With Rydberg Gates, Frank J. Greenhalgh 2011 University of Nevada, Reno

Entangling The Lattice Clock With Rydberg Gates, Frank J. Greenhalgh

Festival of Communities: UG Symposium (Posters)

Knowledge of the exact time is critical to many engineers and planetary experts; unfortunately atomic clocks can't have infinite accuracy by Heisenberg's uncertainty principle. To attain accuracy past the limit we have achieved today, we will design a critical improvement of the atomic clock via the Rydberg gates method. Rydberg gates synchronize the atomic states so that they are more sensitive which will greatly increase the accuracy. This project will introduce fast acting Rydberg gates to an existing atomic clock layout. The Rydberg gates will allow the clock to entangle atoms in less time, thus decreasing decoherence effects on the …


“Magic” Trapping Of Rydberg States For Quantum Information, Muir Morrison, Andrei Derevianko 2011 University of Nevada, Reno

“Magic” Trapping Of Rydberg States For Quantum Information, Muir Morrison, Andrei Derevianko

Festival of Communities: UG Symposium (Posters)

Recent experiments using neutral atoms to manipulate quantum information show promise for constructing a large-scale, practical quantum computer. Achieving such a quantum computer will require less destructive optical traps for the atoms. Using theoretical and computational tools, we consider the feasibility of one possible “magic” trap for rubidium. Preliminary results suggest such trapping may be possible, but more accurate calculations are necessary to reach definitive conclusion.


Dynamical Critical Scaling And Effective Thermalization In Quantum Quenches: Role Of The Initial State, Shusa Deng, Gerardo Ortiz, Lorenza Viola 2011 Dartmouth College

Dynamical Critical Scaling And Effective Thermalization In Quantum Quenches: Role Of The Initial State, Shusa Deng, Gerardo Ortiz, Lorenza Viola

Dartmouth Scholarship

We explore the robustness of universal dynamical scaling behavior in a quantum system near criticality with respect to initialization in a large class of states with finite energy. By focusing on a homogeneous XY quantum spin chain in a transverse field, we characterize the nonequilibrium response under adiabatic and sudden quench processes originating from a pure as well as a mixed excited initial state, and involving either a regular quantum critical or a multicritical point. We find that the critical exponents of the ground-state quantum phase transition can be encoded in the dynamical scaling exponents despite the finite energy of …


Quantum Mechanical Model Of The Hydrogen Atom, Andres Ortiz^, Snehanshu Saha* 2011 Department of Mathematical Sciences, University of Texas at El Paso

Quantum Mechanical Model Of The Hydrogen Atom, Andres Ortiz^, Snehanshu Saha*

COURI Symposium Abstracts, Spring 2011

The quantum mechanical wave function of an object under a certain potential is determined by the Schrödinger equation. It is known that the latter equation can be solved analytically only for a finite number of distinct potentials, being a Coulomb potential one of them. For an electron in a hydrogen atom, we analytically find the angular parts of its wave function by the usual method. Under the appropriate change of variable, the radial part of the equation is turned into a Legendre differential equation whose solutions are Legendre polynomials. Using finite difference method and shooting method taking into account physically …


Modeling Of Solvent Electrostatic Effects, Jose A. Rodriguez Lopez^, Luis Basurto, Tunna Baruah* 2011 Department of Physics, University of Texas at El Paso

Modeling Of Solvent Electrostatic Effects, Jose A. Rodriguez Lopez^, Luis Basurto, Tunna Baruah*

COURI Symposium Abstracts, Spring 2011

The photo-induced charge-transfer process is fundamental to light harvesting in organic donor-acceptor systems. The process is often enhanced when the system is in a polar solvent. The aim of this project is to create a simple, discrete model containing dipoles that can explain the solvent effects, where only dipole-dipole solvent interaction is considered. The goal is to reduce computational complexities and cost. We create a grid of solvents (water) which mimic the solvent’s density; and put one solute (a light-harvesting triad of β-carotene, porphyrin, and C60) at the grid’s center, keeping the grid points 1.5 times the Van der Waal …


Coherent-State Transfer Via Highly Mixed Quantum Spin Chains, Paola Cappellaro, Lorenza Viola, Chandrasekhar Ramanathan 2011 Massachusetts Institute of Technology

Coherent-State Transfer Via Highly Mixed Quantum Spin Chains, Paola Cappellaro, Lorenza Viola, Chandrasekhar Ramanathan

Dartmouth Scholarship

Spin chains have been proposed as quantum wires in many quantum-information processing architectures. Coherent transmission of quantum information in spin chains over short distances is enabled by their internal dynamics, which drives the transport of single-spin excitations in perfectly polarized chains. Given the practical challenge of preparing the chain in a pure state, we propose to use a chain that is initially in the maximally mixed state. We compare the transport properties of pure and mixed-state chains and find similarities that enable the experimental study of pure-state transfer via mixed-state chains. We also demonstrate protocols for the perfect transfer of …


Experimental Violation Of Two-Party Leggett-Garg Inequalities With Semiweak Measurements, Justin Dressel, C. J. Broadbent, J. C. Howell, Andrew N. Jordan 2011 Chapman University

Experimental Violation Of Two-Party Leggett-Garg Inequalities With Semiweak Measurements, Justin Dressel, C. J. Broadbent, J. C. Howell, Andrew N. Jordan

Mathematics, Physics, and Computer Science Faculty Articles and Research

We generalize the derivation of Leggett-Garg inequalities to systematically treat a larger class of experimental situations by allowing multiparticle correlations, invasive detection, and ambiguous detector results. Furthermore, we show how many such inequalities may be tested simultaneously with a single setup. As a proof of principle, we violate several such two-particle inequalities with data obtained from a polarization-entangled biphoton state and a semiweak polarization measurement based on Fresnel reflection. We also point out a nontrivial connection between specific two-party Leggett-Garg inequality violations and convex sums of strange weak values.


Equivalent Dynamical Complexity In A Many-Body Quantum And Collective Human System, Neil F. Johnson, Josef Ashkenazi, Zhenyuan Zhao, Luis Quiroga 2011 University of Miami

Equivalent Dynamical Complexity In A Many-Body Quantum And Collective Human System, Neil F. Johnson, Josef Ashkenazi, Zhenyuan Zhao, Luis Quiroga

Physics Articles and Papers

Proponents of Complexity Science believe that the huge variety of emergent phenomena observed throughout nature, are generated by relatively few microscopic mechanisms. Skeptics however point to the lack of concrete examples in which a single mechanistic model manages to capture relevant macroscopic and microscopic properties for two or more distinct systems operating across radically different length and time scales. Here we show how a single complexity model built around cluster coalescence and fragmentation, can cross the fundamental divide between many-body quantum physics and social science. It simultaneously (i) explains a mysterious recent finding of Fratini et al. concerning quantum many-body …


Establishing Building Recommissioning Priorities And Potential Energy Savings From Utility Energy Data, Kevin P. Hallinan, Philip Brodrick, Jessica Northridge, J. Kelly Kissock, Robert J. Brecha 2011 University of Dayton

Establishing Building Recommissioning Priorities And Potential Energy Savings From Utility Energy Data, Kevin P. Hallinan, Philip Brodrick, Jessica Northridge, J. Kelly Kissock, Robert J. Brecha

Physics Faculty Publications

An energy reduction program for commercial buildings is implemented for a SW Ohio natural gas utility. The aim of this study is to demonstrate that historical utility data for individual building customers, along with knowledge of pertinent building information (square footage, year built, number of floors, height of floors, wall construction type, and use type) available in county auditor databases, could be used to identify the best candidate buildings for recommissioning in terms of energy savings and simple payback. A study is completed for all natural gas customers of a utility in Montgomery and Clinton counties in Ohio. A total …


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